1. Field of the Invention
The present invention relates to a semiconductor device (and method of making the device) and more particularly, a semiconductor device which includes first and second contacts, the first contact being asymmetric with respect to the second contact.
2. Description of the Related Art
FIG. 7 illustrates a conventional semiconductor device 700 (e.g., field effect transistor (FET)). As illustrated in FIG. 7, the conventional device includes a gate 710, source and drain regions 730a, 730b, and contact layers 740a, 740b. As illustrated in FIG. 7 the source and drain regions 730a, 730b conventionally have the same width and depth (e.g., same volume) and are formed of the same material (e.g., the same doped semiconductor material).
In addition, as further illustrated in FIG. 7, the contact layers 740a, 740b conventionally have the same width and height (e.g., volume), and are formed the same distance away from the gate of the FET. In addition, the contact layers 740a, 740b are typically formed of the same material.
The contact layers 740a, 740b are layers of conductive material which are used to electrically connect features in conventional semiconductor devices. For example, in the conventional device 700, the first contact layer 740a may be used to contact the source region 730a, and the second contact layer 740b may be used to contact the drain region 730b. 
The contact layers 740a, 740b may be formed as stressed contact layers which may apply a tensile or compressive stress on the underlying substrate. For example, in the example above, the first contact layer 740a may apply a stress to the source region 730a and the second contact layer 740b may be apply a stress to the drain region 740b. 
The use of stressed contact layers to enhance device (e.g., field effect transistor (FET)) performance is becoming pervasive in advanced silicon complementary metal oxide semiconductor (CMOS) devices.
As pitch is further scaled, the amount of benefit incorporated (e.g., by the use of stressed contact layers) is a complex function of the contact material, contact size, and distance of the contact from the device.